In a semiconductor device manufacturing process in which a laminated structure of an integrated circuit is formed on a surface of, for example, a semiconductor wafer (hereinafter, referred to as a “wafer”) as a substrate, a liquid processing process is provided to process a wafer surface by using a liquid, for example, to remove fine dust or a natural oxide film on a wafer surface by using a cleaning liquid such as, for example, a chemical liquid.
There has been known a supercritical processing method using a fluid in a supercritical or subcritical state (which may also be collectively referred to as a “supercritical fluid”) when removing a liquid or the like attached to the surface of the wafer in the liquid processing process.
However, when performing the supercritical processing on the wafer by using the supercritical fluid, in a pre-process, a dry preventing liquid composed of, for example, isopropyl alcohol (IPA) is first filled on the wafer, the wafer on which the dry preventing liquid has been filled is placed on a holding member positioned outside a container body, and the wafer on the holding member is carried into the container body. Then, the supercritical processing is performed on the wafer inside the substrate processing container by using the supercritical fluid.
After the supercritical processing is completed, the holding member is moved outward so as to discharge the wafer on the holding member outward.
Next, a wafer on which a new dry preventing liquid has been filled is placed on the holding member, and the above-described operation is repeated.
As described above, the dry preventing liquid is filled on the wafer to be placed on the holding member. When the supercritical processing is performed on the wafer inside the substrate processing container, the holding member is also heated to a high temperature. It has been found that, when a wafer on which the new liquid has been filled is placed on the holding member in the state where the temperature of the heated holding member is high, the dry preventing liquid filled on the wafer is dried by the heat from the holding member, and thus, an appropriate supercritical (heating) processing may not be performed on the wafer. See, for example, Japanese Laid-Open Publication No. 2013-12538